Processes and systems for discharging amine byproducts formed in an amine-based solvent

• US 8,563,296 B2
• Filed: 11/24/2010
• Issued: 10/22/2013
• Est. Priority Date: 11/24/2010
• Status: Active Grant

• Current Assignee: UOP Llc (Honeywell International Inc.)
• Original Assignee: UOP Llc (Honeywell International Inc.)
• Inventors: Greer, David W., Ellis, Graham, Zbacnik, Edward, Zhou, Lubo
• Primary Examiner(s): Hanley, Susan
• Assistant Examiner(s): NGUYEN, NGHI V
• Application Number:
  US12/953,865
• Publication Number:
  US 20120125012A1
• Time in Patent Office: 1,063 Days
• Field of Search: 435/257.1, 435/183, 435/821, 435/946, 435/243
• US Class Current: 435/257.1
• CPC Class Codes: B01D 53/1425 Regeneration of liquid absorbents
• CPC Class Codes: B01D 53/1475 Removing carbon dioxide
• CPC Class Codes: C02F 1/20 by degassing, i.e. liberation of dissolved gases degasification of liquids in general B01D19/00; arrangement of degassing apparatus in boiler feed supply F22D
• CPC Class Codes: C02F 2101/38 containing nitrogen
• CPC Class Codes: C02F 2103/18 from the purification of gaseous effluents
• CPC Class Codes: C02F 2209/06 pH
• CPC Class Codes: C02F 2303/16 Regeneration of sorbents, filters
• CPC Class Codes: C02F 3/322 use of algae
• CPC Class Codes: C12M 29/26 Conditioning fluids entering or exiting the reaction vessel
• CPC Class Codes: C12M 43/04 Bioreactors or fermenters combined with combustion devices or plants, e.g. for carbon dioxide removal C12M43/06 takes precedence; recovery of carbon dioxide C12F3/02
• CPC Class Codes: C12M 43/08 Bioreactors or fermenters combined with devices or plants for production of electricity

Abstract

Embodiments of a process for discharging amine byproducts formed in an amine-based solvent are provided. The process comprises the steps of contacting the amine-based solvent with flue gas comprising carbon dioxide, oxygen, nitrogen, NO_x, SO_x, or mixtures thereof to form a carbon dioxide-laden amine-based solvent that contains the amine byproducts. Carbon dioxide is separated from the carbon dioxide-laden amine-based solvent to form a carbon dioxide-depleted amine-based solvent. The amine byproducts from the carbon dioxide-depleted amine-based solvent are fed to an algae source.

Claims

1. A process for discharging amine byproducts formed in an amine-based solvent, the process comprising the steps of:

a) contacting the amine-based solvent with flue gas comprising carbon dioxide, oxygen, nitrogen, NO_x, SO_x, or mixtures thereof to form a carbon dioxide-laden amine-based solvent that contains at least one amine byproduct selected from the group consisting of bicine, thiosulfates, thioureas, polysulfides, and mixtures thereof;

b) separating carbon dioxide from the carbon dioxide-laden amine-based solvent to form a carbon dioxide-depleted amine-based solvent; and

c) feeding at least one of the amine byproducts from the carbon dioxide-depleted amine-based solvent to an algae source.

2. The process according to claim 1, wherein the amine-based solvent comprises an amine selected from the group consisting of monoethanolamine, diethanolamine, piperazine, diisopropanolamine, triethanolamine, 2-amino,2-methyl,1-propanol, diamines, methyldiethanolamine, tertiary amines, and mixtures thereof.

3. The process according to claim 1, further comprising the step of separating the amine byproducts from the carbon dioxide-depleted amine-based solvent to form a regenerated amine-based solvent and an amine byproducts effluent, and wherein the step of feeding includes introducing the amine byproducts effluent to the algae source.

4. The process according to claim 3, wherein the step of separating carbon dioxide includes forming a carbon dioxide rich stream from the carbon dioxide separated from the carbon dioxide-laden amine-based solvent, and the process further comprising the step of introducing the carbon dioxide rich stream to the algae source.

5. The process according to claim 3, wherein the step of contacting the amine-based solvent with the flue gas occurs in a carbon dioxide absorber unit, and the process further comprising the step of introducing the regenerated amine-based solvent to the carbon dioxide absorber unit.

6. The process according to claim 1, wherein the step of feeding includes introducing the carbon dioxide-depleted amine-based solvent to the algae source, the carbon dioxide-depleted amine-based solvent containing the amine byproducts.

7. The process according to claim 6, wherein the step of feeding includes introducing a quantity of the carbon dioxide-depleted amine-based solvent to the algae source, the quantity sufficiently limited so as to not cause the algae source to have a pH exceeding about 11.

8. The process according to claim 1, wherein at least a portion of the amine byproducts are nutrients for algae in the algae source, and the process further comprising the step of digesting the nutrients with the algae.